Sonic driving system for bendable lines



sept. 5, 1967 A G, BOBINE, JR 3,339,646

. SONIC DRIVING SYSTEM FOR BENDABLELINES Filed Feb. 1, 1965 4sheets-Sheet 1 RESERVOR ATTORNEY Siept. 5, 1967 A. G. BOBINE, JR

SONIC DRIVING SYSTEM FOR BENDABLE LINES 1965 4 Sheets-Sheet 2 Filed Feb.

NVENTOR.

' ALBERTG. BOD|NE,JR. BY

ATTORNEY sePf- 5, 1967 y A. G. BOBINE, 1R 3,339,646

SONIC DRIVING SYSTEM FOR BENDABLE LINES Filed Feb` l, 1965 4Sheets-Sheet 5 FIG. 3

iwf/@4.4%

ALBERT G. BODINE, JR.

ATTORNEY Sept 5, 1967 A, G; BOBINE, JR

SONIC DRIVING SYSTEM FOR BENDABLE LINES 4 Sheets-Sheet 4 Filed Feb.

INVENTOR.

ALBERT G. BODINE, JR.

FIG. 6

ATTORNEY United States Patent O 3,339,646 SONIC DRIVING SYSTEM FORBENDABLE LINES Albert G. Bodine, Jr., 7877 Woodley Ave., Van Nuys,Calif. 91406 Filed Feb. 1, 1965, Ser. No. 429,490 Claims. (Cl. 175-62)ABSTRACT oF THE DrscLosURE A line to be driven through the groundhorizontally is passed through a roller guide mechanism which guides itfrom a generally Vertical ground entry angle to the desired horizontaldrive direction. Sonic vibrational energy s applied to the line, tocause elastic vibration thereof, by means of a mechanical sonicoscillator which is carried up and down on guide tracks along with meansfor driving the line through the roller guide mechanism. The sonicenergy stress relieves the line material and reduces friction, therebymaking such material readily yieldable to the bending force andfacilitating the movement of the line through the ground.

This invention relates to. a sonic driving system for bendable lines,and more particularly to such a system for facilitating the routing ofsuch lines through the ground.

Lines such as power and telephone cables and water conduits often haveto be routed underground in situations where the tearing up of thesurface for such routing is impossible or at best inconvenient andexpensive. It sometimes is feasible to route lines through the ground byburrowing or trenching techniques. The burrowing of lines, however,often poses a formidable task, especially where pavement, buildings,hard earth and/or rock conditions are encountered.

It has been found, as described in my co-pending application Serial No.198,783, filed May 31, 1962, that lines can be driven through the groundwith relative ease if while being so driven they are excited with sonicvibrations preferably at a frequency which sets up a resonant vibrationof such lines. Such sonic vibrations effectively iluidize granular earthand penetrate rock material by virtue of the elastic fatigue, causedboth by the cyclic compressional and tension states induced therein,thus making for reduced wall friction and a clear path for the conduitto progress therethrough. Along these lines, my Patent No. 2,975,846describes the use of such techniques for driving piles.

The device and method of this invention provide improved means forutilizing sonic techniques in driving lines underground whereby suchlines can be driven into the ground from the surface at an anglerelative to the horizontal direction in which the line is to be drivenand then bent back to assume the desired horizontal direction. The sonicenergy is utilized in the device and method of this invention inimplementing the bending operation in addition to its function inpenetrating and lluidizing the ground. The provision of means forenabling entry into the ground from above has two primary advantages.

First, the need for a large lead area is eliminated as there A is noneed to dig a ditch or trench to enable the initial feeding of the lineat a point below the normal ground level in the desired horizontaldirection. Secondly, a vertical component is added to the driving actionthus adding the force of gravity to the force bias, to aid in thedriving of the line.

The desired end results are achieved in the device and method of theinvention by providing a forming path such as a roller guide mechanismwhich guides the line from its ground entry angle to the desiredhorizontal Hce drive direction. Such curving of the line by the guidemechanism is facilitated by virtue of sonic vibrations applied to theline preferably at substantially a resonant frequency thereof to stressrelieve the line material, and to reduce friction through the formingpath, thereby making such material readily yieldable to the bendingforce. Sonic vibrations are applied to the line by means of a mechanicalsonic oscillator which is carried up and down on guide tracks along withthe means for driving the line through the roller guide mechanism.

It is therefore an object of this invention to facilitate the running oflines through the ground.

It is a further object of this invention to enable the running of linesthrough the ground from a starting position at ground surface.

It is still another object of this invention to provide a device andmethod whereby sonic energy is utilized to enable the driving of a linehorizontally through the ground in a starting direction which is at anangle with respect to the ground surface.

It is -still a further object of this invention to minimize the leadarea required for driving lines through the ground.

It is still another object of this invention to provide a method anddevice for utilizing sonic energy to both drive a line through theground and to bend such line so that its direction of travel is changedfrom an initial direction.

Other objects of this invention will become apparent from the followingdescription taken in connection with the accompanying drawings, ofwhich:

FIG. l is a schematic View illustrating the device of the invention inoperation,

FIG. 2 is an elevation View, partially in cross section, illustrating anoscillator mechanism that may be utilized in the device of theinvention,

FIG. 3 is an elevation view partially in cross section illustrating apreferred embodiment of a power drive and bending mechanism which may beutilized in the device of the invention,

FIG. 4 is a cross-sectional view taken along the plane indicated by 4-4in FIG. 3,

FIG. 5 is an elevation cross-sectional view of the collar cla-mp releasemechanism utilized in the drive mechanism illustrated in FIG. `3,

FIG. 6 is a cross sectional view of a mandrel mechanism which may beutilized to facilitate the driving of flexible conduit with the deviceof the invention, and

FIG. 7 is a schematic drawing of a hydraulic control system which may4be utilized with the device of the invention.

In order to properly analyze the device of the invention Iit is helpfulto resort to an analogy between an electrical oscillating resonantcircuit and a mechanically vibrating elastic resonant circuit. 'The useof such an analogy is well known to those skilled in the art and isdescribed for example in Chapter 2 of Sonics by Hueter and Bolt,published lin 1955 by'lohn Wiley and Sons. Thus, driving force, F, isanalogous to voltage, E, velocity of vibration, u, is analogous toelectric current, z', compliance, Cm, is analogous to capacitan-ce, Ce,Mass, M, is analogous to inductance, L, and mechanical resistance suchas friction, Rm, is analogous -to electrical resistance, R. By such ananalogy, it can be shown that if a member is elastically vibrated by asinusoidal force, F0 sin wT that where,

Zm=the mechanical impedance of the member being driven Rm=the effectivemechanical resistance of the circuit being driven M :the mass of theobject being driven Cm=the effective elastic compliance of the objectbeing driven u--velocity of vibration of object w=21rf, where f is equalto the frequency of vibration.

Where, 1M is equal to 1/ wCm, a resonant condition eX- ists, and theeffective mechanical impedance, Zm, is equal to the mechanicalresistance, Rm, the reac-tive impedance components, wM and 1/ wCm,lcancelling each other out. Under such a resonant condition, velocity ofvibration, u, is at a maximum, effective power factor is unity, andenergy is most efficiently delivered to the object being Vibrated. It issuch a high eficien-cy resonant condition in the line -being driven thatis preferably utilized in the method and device of this invention toachieve the desired end results.

It is to be noted by reference to Equation 1 that velocity of vibration,u, is highest where impedance, Zm, is lowest and vice versa. Therefore,a high impedance load will tend to vibrate at relatively low velocityand vice versa. At an interface Ybetween high and low impedanceelements, a high relative movement results by virtue of such impedance4mismatch which is in `an electrical circuit results in a high reectedwave. On the other hand, energy is most efficiently transmitted throughmatched impedance elements, just as in an electrical circuit.

As the sharpness of .resonance of an electrical circuit is determined bythe Q of the circuit (indicative of the ratio of energy stored to theenergy used in each cycle), so also the Q of a mechanical resonantcircuit has the same significan-ce and is equal to the ratio between wMand wRm. Thus, a high Q resonantly Vibrating system is capable ofproducing considerable cyclic motion.

It can also be shown that the acceleration of a sinusoidally vibratingmass is a function of the square of the frequency of vibration. Thus,even at moderately high vibration frequencies, very high accelerationsand forces can be achieved.

lt should be constantly kept in mind when considering Equation l thatthis equation represents the total effective resistance, mass, etc., inthe mechanical circuit driven by the oscillator and the parametersindicated are generally distributed throughout the system rather thanbeing lumped in any one component or portion thereof.

Referring now to FIG. 1, a schematic drawing illustrating the operationof the device of the invention is shown. Conduit 11 which is t-o bedriven through the ground 18 is fed through oscillator and hold-release-assembly 15 in au initial direction which is at an angle with respectto the ground surface plane. From oscillator and holdrelease assembly1S, conduit 11 is fed through roller `guide assembly 17 where it is bentfrom its initial direction of travel to a final direction of travelsubstantially parallel to the ground surface plane. Roller guideassembly 17 includes support apron 64 which has a channel 22 formedtherein for guiding the conduit and rollers 69 for facilitating thepassage of the conduit through the channel.

Mechanical oscillator and hold-release mechanism 15 is fixedly mountedon .carriage 16, and carriage 16 is slidably supported on support frame14. Drive mechanism 19 reciprocally drives carriage 16 in the directionsindicated by arrows 25. Means are provided in mechanical oscillator andhold-release assembly 15 for grabbing conduit 11 during the downwardtravel of carriage assembly 16, and releasing such conduit during theupward travel the-reof, thereby driving the conduit downwardly in theinitial direction of travel.

A mechanical oscillator is included in assembly 15 for impartingmechanical vibrations to conduit 11 along the longitudinal -axisthereof. Such vibrations may be in the sonic frequency range of, forexample, between 300 and 500 cycles per second. Such vibrations arepreferably of a frequency which will cause resonantvibration of conduit11 whereby standing waves are set up in the line.

Under such resonant conditions, as can be seen from Equation 1, theeffective compliant reactive and mass reactive components cancel eachother out so that the effective mechanical impedance, Zm, is equal tothe rnechanical resistance, Rm. This provides for maximum velocity ofvibration, u, with most efficient transfer of vibration energy to theconduit. The high enengy vibration of conduit 11 stress relieves thematerial of the conduit so that it is readily bent in roller guidemechanism 17 to change its direction of travel as desired, and at thesame time effectively fluidizes the ground through which the conduitpasses by virtue of the elastic fatigue and liuidization in the earthenmaterial caused by the cyclic compressional land tension states inducedtherein. The vibration of the conduit also facilitates passage of sa-methrough the roller guide mechanism, this by virtue of the high relativevibrational motion between the two, This results from the impedancemismatch at the interface between the resonant low impedance conduit andthe relatively high impedance earth supported guide mechamsm.

As the effective length of conduit 11 increases as it is driven furtherinto the ground, the frequency of the orbital mass oscillator tends toautomatically adjust with the changing load to the resonant frequencythereof thus assuring optimal operation with standing waves of multiplesof a half wavelength present along the line at all times. The oscillatorhas a low impedance, high velocity output, and thus, vibration velocity(u) antinodes tend to appear at the oscillator and at the far end of theline. This provides a high velocity low impedance condition at thedriving end of the line. ln view lof the high impedance presented by thehigh mass earth, the earth mass, while being effectively stressed by thevibration energy, tends to vibrate at a relatively low velocity ascompared with the end of the line. This high relative movement betweenthe line and the earth tends to enhance the fluidation of the soil andpassage of the line therethrough.

Referring now to FIG. 2, a mechanical oscillator that may be utilized inthe device of the invention is illustrated. The os-cillator shown inFIG. 2 is similar in configuration to that described in myaforementioned copending application Serial No. 198,783. This ty-pe oforbiting mass oscillator has the unique property of automaticallyadjusting its rotation frequency with load changes to maintain resonantvibration of the load. The oscillator, in effect, becomes part of theresonant circuit and tends to lock in at the resonant frequency of t-hevibrating member being driven thereby.

Power plant 20 which is mounted on support frame 21, and which mayinclude a gasoline engine, provides output arotation of shaft 23. Shaft23 is connected t-o rotatably driven lgear wheel 24a. Gear wheel 24a iScoupled to rotatably drive gear wheel 24b in an opposite direction. Thusoutput coupling 26a which is connected to gear lwheel 24a is rotatably`driven in a first direction, and output coupling 2Gb which is connectedto gear Wheel 24b is rotatably driven in an opposite direction. Couplingshaft 32a is connected to -gear coupling 26a by means of universal joint30a. Coupling shaft 32a is slidably mounted within tubular shaft 33a toform a slip spline joint therewith such that shaft 32a rotatably drivesshaft 33a but so that the two shafts can move relative to each otheralong their longitudinal axes. Gear coupling 2Gb, universal joint 30b,coupling shaft 32b and tubular drive shaft 33b are similar inconfiguration to the similarly identified units 26a, 30a, 32a and 33a,just described. Shafts 33a and 33b are coupled by means of universaljoints 35a and 35h respectively to associated gear shaft 41a and 41b.Fixedly attached to gear shaft 41a is gear Wheel 38a and fixedlyattached to :gear shaft 41b is gear wheel 38h. Rotors 40a and 40h arerotatably mounted on their associated gear shafts 41a and 41b.

Gear wheels 38a and 38b ride around on ring gears 37a and 37brespectively, which are attached to the inner walls of associatedraceways 39a and 3919 formed in casing 42. Rotors 40a and 40b arecarried along with their associated gear wheels and gear shafts, gearshafts 41a and 41b rolling around respective pins 46a and 46b formed incase 42. Rotors 40a and 40b thus are rotated about their associatedraceways 39a and 39h.

The rotors are initially positioned so that lthey will producesubstantially equal and opposite forces on casing 42 when in theposition indicated in FIG. 2 and positions 180 removed therefrom butwill produce additive forces when they are in positions 90 removed fromthe position indicated in FIG. 2 (such as shown, for example, in FIG.3). Thus, as best can be seen by reference to FIG. 3, strong vibrationaloscillations are produced in casing 42 along the longitudinal axis ofoon-duit 11 with vibrational forces normal to this axis beingsubstantially cancelled out.

Referring now to FIGS. 3 and 4, a carriage and hydraulic drive mechanismwhich may be utilized in the device of the invention is illustrated.Oscillator and holdrelease mechanism 15 is mounted on cam'age 16. Casing42 of the oscillator is supported on the carriage by means of vibrationisolators 43a and 43b an-d 44 which minimize the transfer of vibrationenergy from the oscillator to the adjacent components. Isolators 43a and43b and 44 may be of neoprene or any other suitable isolating material.

Carriage 16 has a pair of guide channels 66a and 66b formed alongopposite edges thereof. Fixedly attached to frame member 14 are tracks67a and 67b on which guide channels 66a and 6617 are slidably iitted.Hydraulic jacks 48a and 48h are fixedly mounted on frame 14 by means ofclamps 52a and 52b. The drive rods 50a and 50b of these jacks areattached at the ends thereof to carriage 16. When jacks 48a and 48h areappropriately actuated, as to be explained in connection with FIG. 7,carriage 16 is reciprocally driven up and down along the guide tracks67a and 67b. The direction of drive is automatically reversed whencarriage 16 strikes limit switches 60a and 88a mounted on the frame, andsimilar limit switches 60'b and 8812 (not shown) at the end of downwardtravel.

Collet clamp mechanism 45, which is described in detail in connectionwith FIG. 5, is provided to grab conduit 11 during the downward travelof carriage 16 and to release the conduit during the upward travel ofthe carriage. The conduit is thus driven in a downward direction by .thecarriage mechanism. It is to be noted that such downward drive has theadditional force of gravity behind it, in addition to the force providedby the jacks 48a and 48h, this as contrasted with the initial horizontaldrive described in my co-pending application Ser. No. 198,783.

Referring now to FIG. 5, the details of the collet clamp mechanism 45are shown. As to be explained in connection with FIG. 7, this mechanismoperates in response to a hydraulic control, the same control whichoperates the jack 48a and 48b. Collet clamp mechanism 45 is attached tooscillator casing 42, the mechanical vibrations of the oscillator thusbeing transmitted to the casing 72 of the collet clamp mechanism.Mounted in casing 72 is conical slotted collet 71 which includes aplurality of resilient fingers 71a. Casing 72 is mounted on carriage 16on vibration isolator 44, thus preventing the dissipation of thevibration energy of the oscillator in the surrounding equipment.Slidably mounted in casing 72 is cam member 75 which is externallyconcentric with collet 71.

While carriage 16 is being driven downwardly, a hydraulie input signalis fed through line 78 to channel 80 so to drive cam member 75 to theright as shown in FIG.

5. In this position, cam surface 73 of cam member 75 v inwardlycompresses fingers 71a so that they tightly grab the conduit 11, therebyholding such conduit to the carriage mechanism as it is movingdownwardly. When the carriage reaches the end of its downward travel,the hydraulic drive is reversed to provide a hydraulic input in line 77to channel 79 to drive cam member 75 to the left. In such position, camsurface 73 no longer depresses fingers 71a, and the conduit is thusreleased during the upward travel of the carriage mechanism. O ringseals 82 are provided to prevent hydraulic leakage. The vibration energygenerated by the oscillator is transmitted from oscillator casing 42through collet casing 72 and collet ngers 71a to lconduit 11.

Referring now to FIG. 7, a hydraulic control system i which may beutilized to implement the hydraulic drive and hold-release mechanism isillustrated. The hydraulic action is started by closing electricalswitch 87. This connects electrical power from generator 86 to the armsof limit switches 60 and 88. During the downward travel of the carriage,limit switch 88 is closed (as shown in the figure) and provides powerto, solenoid valve 90a. With solenoid valve 90a actuated, hydraulic uidis pumped from reservoir 84 by pump 83 through line 93 and the solenoidvalve to lines 54a, 54b and 78. The fluid in lines 54a and 54b drivesjacks 48a and 48h so as to provide downward travel of carriage 16. Thefluid drive in line 78 provides the drive signal for cam member 75causing the conduit 11 to be held to the carriage mechanism as explainedin connection with FIG. 5. When the carriage mechanism reaches the endof its downward travel, switch 60 is closed and switch 88 is opened byvirtue of mechanical actuation by carriage 16. This causes solenoidvalve 90b to be energized and solenoid valve 90a to be deenergized.Under such conditions, hydraulic drive is provided through solenoidvalve 90b to lines 55a and 55b to reverse the direction of jacks 48a and48b, thus causing the carriage mechanism to be driven upwardly.Simultaneously, hydraulic drive is provided through line 77 to drive cammechanism 75 as described in connection with FIG. 5, so as to releasethe conduit. In this fashion, the conduit is automatically drivendownwardly by virtue of the reciprocating movement of the carriagemechanism.

Referring now to FIG. 6, a mandrel device is shown which may be utilizedwith the device of the invention where a flexible conduit such as aplastic line is to be driven through the ground. Mandrel member 102,which is .preferably metallic and while bendable in the guide mechanismof the device of the invention, has a rigid quality, is inserted intoflexible line 101. The end of the line is capped by means of cappingassembly which provides a strong drive point and which prevents dirt andother foreign matter from entering the hollow conduit. Capping assembly100 includes an external capping member 103, the end of which grips theouter wall of conduit 101 and an inner member 104 which grips the innerwall of the conduit. Inner and outer members 103 and 104 may be joinedtogether by spot welding or any other suitable means. Mandrel 102 ispreferably of a metallic material having high vibration efficiency (highQ) to enable most effective utilization of the vibration energy.

The device and techniques of this invention thus provide a simple yethighly elective means for driving a conduit through the ground with aninitial downward travel direction. The use of such an initial downwarddrive obviates the necessity for making a large excavation as requiredwith completely horizontal drive techniques and greatly facilitates theentire operation.

While the device and method of the invention have been described andillustrated in detail, it is to be clearly understood that this isintended by way of illustration and example only and is not to be takenby way of limitation, the spirit and scope of this invention beinglimited solely by the terms of the following claims.

I claim:

1. A device for driving a bendable elongated line through the groundcomprising guide means for bending said line to change the direc- 7 tionof travel thereof from a first initial direction to a second finaldirection,

means for driving said line in said initial direction, and

sonic oscillator means for vibrating said line to both fluidize theground through which said line is being driven and to stress relieve thematerial from which said line is fabricated so as to facilitate thebending of said line.

2. The device as recited in claim 1 wherein the'output frequency of saidoscillator is such as to vibrate said line resonantly.

3. A device for driving a through the ground comprising guide means forbending said line to change the direction of travel thereof from aninitial direction at an angle with respect to the ground surface planeto a final direction substantially parallel to the ground surface plane,said guide means including a curved guide channel for said line,

means for driving said line in said linitial direction, and

sonic oscillator means for vibrating said line resonantly to both uidizethe ground through which said line is being driven and to stress relievethe material from which said line is fabricated so as to facilitate thebending of said line.

4. A method for driving a ground comprising driving the line downwardlyfrom the ground surface at an angle with respect to the ground surfaceplane,

bending said line from its downward drive angle to a desired final drivedirection, and

while said line is being driven, applying sonic vibrations thereto tosimultaneously fluidize the ground through which the line is beingdriven and to stress bendable elongated line bendable line through therelieve the material from which said line is fabri-V cated so as tofacilitate the bending of said line from its downward drive angle to thedesired final drive direction.

5. The method as recited in claim 4 wherein said line is vibrated at afrequency which causes resonant vibration thereof.

6. A device for driving a bendable line through the ground comprisingroller guide means for bending said line from an initial direction oftravel downward from the surface of theY ground to a direction of travelsubstantially parallel to the surface of the ground,

means for driving said line downwardly through said roller guide means,and

mechanical sonic oscillator means for resonantly vibrating said line,whereby the vibrations in said line effectively fluidize the groundthrough which the line is being driven and stress relieve the materialfrom 8 which said line is fabricated so as to facilitate the bending ofsaid line.

7. A device for driving a ground comprising roller guide means forbending said line from an initial direction of travel downward from thesurface of the ground to a direction of travel substantially parallel tothe surface of the ground,

means for driving said line downwardly through said roller guide meansincluding a carriage mechanism, means for slidably supporting saidcarriage mechanism for reciprocal motion along an axis extending insubstantially the initial direction of travel of said line, means fordriving said carriage mechanism reciprocally along said axis, clampmeans fixedly mounted on said carriage mechanism and means for actuatingsaid clamp means to clamp said line to said carriage mechanism when saidcarriage mechanism is moving downwardly and to release said line fromsaid carriage mechanism when said carriage mechanism is moving upwardly,and

mechanical sonic oscillator means for vibrating said line,

whereby the vibrations in said line effectively fluidize the groundthrough which the line is being driven to facilitate the bending of saidline.

8. The device as recited in claim 7 wherein said mechanical oscillatormeans is mounted on said carriage mechanism and connected tovibrationally drive said clamp means.

9. The device as recited in claim 7 wherein said oscillator meansvibrates said clamp means and said line at a frequency which issubstantially the resonant frequency of the effective impedancepresented thereby.

10. The device as recited in claim 7 wherein said means for reciprocallydriving said carriage mechanism comprises a fluid drive system, saidmeans for actuating said clamp means being connected to operate inresponse to said drive system.

bendable line through the References Cited UNITED STATES PATENTS2,296,161 9/1942 Hall 175-82 X 2,548,616 4/1951 Priestman et al. 175-1032,644,669 7/1953 Curtis et al. 175-61 X 2,942,849 6/ 1960 Bodine 175-552,975,846 3/ 1961 Bodine 175-19 3,116,781 1/1964 Rugeley et al. 175-103X 3,182,732 5/1965 Earnest 175--62 X CHARLES E. OCONNELL, PrimaryExaminer.

R. A. FAVREAU, Assistant Examiner.

1. A DEVICE FOR DRIVING A BENDABLE ELONGATED LINE THROUGH THE GROUNDCOMPRISING GUIDE MEANS FOR BENDING SAID LINE TO CHANGE THE DIRECTION OFTRAVEL THEREOF FROM A FIRST INITIAL DIRECTION TO A SECOND FINALDIRECTION, MEANS FOR DRIVING SAID LINE IN SAID INITIAL DIRECTION, ANDSONIC OSCILLATOR MEANS FOR VIBRATING SAID LINE TO BOTH FLUIDIZE THEGROUND THROUGH WHICH SAID LINE IS BEING DRIVEN AND TO STRESS RELIEVE THEMATERIAL FROM WHICH SAID LINE IS FABRICATED SO AS TO FACILITATE THEBENDING OF SAID LINE.